Abnormal platelet survival and function have been postulated to play a role in the accelerated atherosclerosis seen in familial hypercholesterolemia. In order to test this hypothesis, platelet survival measured by radiochromium and platelet aggregation were determined in a series of patients with marked hypercholesterolemia. Decreased platelet survival has been found, thus implicating the platelet as a possible contributor to the atherosclerosis associated with this disorder. BIBLIOGRAPHIC REFERENCE: Corash, L., Schaefer, E., Poindexter, E., Andersen, J.: Platelet Function and Survival in Familial Hypercholesterolemia. Circulation 54: II-117, 1976.